c. 5600 BC: Beginning of the desertification of North Africa, ultimately leading to the creation of the Sahara desert. This process may have spurred migration to the region of the Nile in the east, thereby laying the groundwork for the rise of Egyptian civilization.

c. 5600 BC: According to the Black Sea deluge hypothesis, the Black Sea floods with salt water. Some 3000 cubic miles (12,500 km3) of seawater is added, significantly expanding the body of water and transforming it into a sea from a fresh-water landlocked lake.